Granite-working tool



E. A. CHASE GRANITE WORKING TOOL July 29 1924.

Original Filed Feb. 11 1921 Patented July 29, 1924.

onirssra'rss annoy ALBERT CHASE, or NORTHFIELD, vnniuonr.

GRANITE-WORKING TOOL.

Original application filed February 11, 1921, Serial No. 444,221 Divided and this application filed I May 29, 1923. Serial No. 642,363.

To all whomitma-y ooncem: A 7

Be it known that I. rJLRoY A. CHASE, a

citizen of the United States, residing at" Northfield, in the county of Washington and State of Vermont, have invented a new and useful Granite-Working Tool, of which the following is a specification.

This application is a division of my application Serial No. 444,221, filed February 11, 1921, on a granite working machine.

This invention relates particularly to an improved tool forremoving stock from the V 'surfaceof large blocks of granite or other.

similar material, and for quickly and eco-' nomically producing a relatively smooth surface thereon.

It is well understood in the art of stone finishing that granitecannot be successfully subjected to the action of cutting tools but that surplus material must be removed by a crushing or breaking process in which there is no substantial sliding movement between 1 ---the work and the tool." In this respect, the finishing of granite is quite different from the finishing of marble or other soft stones.

Accordingly, my invention consists particularly in. the provision of an improved and novel granite working tool so construct- F ed that it will act by a crushing or breaking action rather than by cutting the stone.

To utilize the advantages of my improved tool, provision must be made: for relative movement between thetool and the work andthis result may be conveniently attained by 5 mounting the stone in a chuck for rotation in a large and heavy type of lathe.

In the form of my invention herein shown,

I provide a tool comprising a plurality of discs having bevelled edges and mounted for free and independent rotation upon a movable tool carriage or table. The discs are progressively increased in size rearward ly from the face of the stone and the spaces between the discs are also preferably pro- 5 gressively increased, providing greater clearance for the larger pieces of stone which are removed by the larger rear or outer discs.

A further feature of my invention pertains to the provision of improved bearings for the discs, adapted to resist the severe strains to which the discs are subjected when in operation.

My invention is fully shown in the drawings in which- Fig- 1 is a side elevation, partly ins'ection,

'of my improved granite working tool; and

' belt 14 running over a pulley 15 on'the shaft 11. A tool carriage l6 is mounted to slide axially of the shaft 11 on a table 18 and may be adjusted thereon by'a screw 19 and hand wheel 20,. The table'18 is movable on guides 21 by a screw 22 which may be rotated man ually or automatically in any suitable manner.

The tool carriage 16 is provided with bearing casing 40 in which a supporting shaft 51 is rotatably mounted. The axis of the shaft 51 is preferably disposed at an angle2to the shaft 11, as'clearly indicated in,

relatively small double-bevel disc 50 is mounted on a shoulder 55 of the shaft 51 and is held against a flange 56 on said shaft by a clamping nut 57.v A key 58 may be a ded to prevent relative rotation of the disc and shaft. A bushing 59 and bearing sleeve 52 are clamped on the shaft 51 by lock nuts 60 and the entire assembly is rotatably supported in a pair of antifriction thrust bearings 53 and 54 within the bearlng casing 40.

Additional discs 62, 63 and 64 are mounted on the bushing 59 and the discs 62 and 63 are provided with spacing plates 65 and 66. Ball bearings 67 are introduced between adjacent surfaces of the discs and spacing plates and also at the rear of the outer disc The bushing 58 is commonly a short section of ordinary pipe or tubing which is of relatively soft material and upon which the hardened steel discs 62, 63 and 64 will rotate with very little wear. The bushing 58 may be very easily and cheaply replaced,

. thus greatly reducing the cost of up-keep.

The provision of anti-friction. bearings great importance, as it permits the discs to rotate freely under all circumstances, no matter how great pressure they may sustain. The edges of the discs wouldbe very quickly destroyed by any relative sliding movement between the discs and the extremely hard surface of the granite and consequently this provision for insuring free rotation of the discs under all conditions is very essential.

The actionof the several discs is clearly shown in Figs. '1 and 2, from which it appears that the outer disc 64; commonly engages the stock first, removing the portions projecting beyond its cutting plane in rel atively large pieces. The other discs 63, 62 and thereafter successively engage the stone and remove layers of decreasing thickness from the face thereof. The disc 50 removes a relatively thin layer only and leaves limited to the details herein disclosed other Wise than as set forth m the claims, but What I claim is:

1. A granite working tool comprising a shaft, a supporting bearing in which said shaftis rotatably mounted, a work engaging disc mounted in fixed angular relation on said shaft, and additional discsmountedf'or free and independent rotation of said shaft.

2. A granite Working tool comprising a shaft, a sup-poiting bearing in which saidshaft is rota-table, 'a work engaging disc fixed to the-end of saidsh-aft, a plurality of discs freely rotatable on' said shaft, and anti-friction devices effective to resist side thrust on said discs.

3. A granite working tool comprising a shaft, a supporting bearing in which said shaft is rotatably mounted, a work engaging disc mounted in fixed angular relation on said shaft, a bushing on said shaft,'additional discs freely and independently rotatable on said bushing, and means to secure said bushing on said shaft.

A granite Working too-l comprising: a shaft having a flange near one end thereof, a work engaging disc, means to clamp said disc against one side of said flange, a bushing, means to clamp said bushing againstthe opposite side of said flange, and additional discs freely and independently r'otatable on said bushing.

5. A granite working tool comprising a shaft having a flange atone end thereof,

a work engaging disc, means to clamp sai'd' disc against one side of said flange, a. bushing, means to clamp said bushing, against the oppositeside of said flange, additional discs freely and independently rotatable on said bushing, and anti-friction: devices effective to resist side thrust on said discs.

A granite working tool comprising shaft, a supporting bearing casing in which said shaft is rotatably mounted, aworlr en gaging disc mounted in fixed angular relation on said shaft, a bushing on said shaft,

additional disc-s freely and independently rotatable on said bushing, a bearing sleeve on said shaft, means to secure said bushing and said sleeve on said shaft,and anti-friction thrust bearing elements between said supporting casing and said bearing sleeve.

In testimony whereof have hereunto affixed my signature.

ELROY ALBERT CHASE. 

